For example, as disclosed in the following Patent Document 1, an error rate measuring apparatus is conventionally known as an apparatus which transmits a test signal including fixed data to a device under test such as a photoelectric conversion component, and measures a bit error rate (BER) by comparing a measured signal which is input through the object to be measured with a reference signal which is a standard on a bit basis.
Meanwhile, as a device under test of this type of error rate measuring apparatus, in a device compliant with digital signal transmission standards such as PCIeGen 4.0, USB 3.0/3.1, Thunderbolt, or the like, for example, in order to evaluate the characteristics of a test board for each transmission standard, it is necessary to introduce an ISI calibration channel which is a test fixture simulating a prescribed transmission line loss, in input to a test board.
However, the amount of loss of the ISI calibration channel varies according to transmission standards. Therefore, the user needs to prepare a loss board of the ISI calibration channel conforming to the transmission standard separately from the test board for each transmission standard.